An Amateur Question why Engineering?

I know that this might cause a lot of flaming, but I really want to know.

Engineering is a branch of application in Science.

So my question is, if a person has a Ph.D in Chemistry, Physics, Mathematics, and Biology, would he or she be able to do a job normally needed for a Engineer that requires a Ph.D?

Or can someone with a Ph.D in Physics and Mathematics would be able to do an Engineer's job?

If not, why? If being a wielder of a Ph.D, doesn't that mean he or she should know everything in that field? And since Engineering is part of that, should he or she be able to do that job without the need for the degree?

A PhD does not mean that someone knows everything in a field, just that they were capable of getting to the forefront of knowledge in the field, and were able to extend human knowledge in that field to some degree.

A PhD in physics does not know all of physics, but might be expected to be able to learn pretty much anything in physics pretty rapidly. However, someone with a degree in Civil Engineering is expected to know how to do pretty much everything in Civil Engineering.

In other words, a civil engineer would be expected to know how to build a bridge. While bridge building might fall under the realm of physics, a PhD in physics who primarily studied Optics might not be a good bet for a bridge builder.

Or can someone with a Ph.D in Physics and Mathematics would be able to do an Engineer's job?

No, because they do not have the domain knowledge. Physics and math phds (even experimental and applied ones) are still much more theoretical than the average engineers job. There are lots of old jokes about the differences between engineers, physicists, and math people, but a lot of those jokes are routed in how the different disciplines approach to any problem. Plus taking some circuits in a physics course does not mean you'll do well with complex circuits with devices more complicated than resisters and inductors (which is what the rest of the EE circuits route is about, and even then people specialize into digital or analog.)

If being a wielder of a Ph.D, doesn't that mean he or she should know everything in that field?

Why does everyone have that misconception? A Ph.D means you've got enough domain knowledge to pass your quals (so you've got a competent enough understanding of your field to do your research properly) and a ton of knowledge about whatever your dissertation topic is. That's all.

No, because they do not have the domain knowledge. Physics and math phds (even experimental and applied ones) are still much more theoretical than the average engineers job. There are lots of old jokes about the differences between engineers, physicists, and math people, but a lot of those jokes are routed in how the different disciplines approach to any problem. Plus taking some circuits in a physics course does not mean you'll do well with complex circuits with devices more complicated than resisters and inductors (which is what the rest of the EE circuits route is about, and even then people specialize into digital or analog.)

Why does everyone have that misconception? A Ph.D means you've got enough domain knowledge to pass your quals (so you've got a competent enough understanding of your field to do your research properly) and a ton of knowledge about whatever your dissertation topic is. That's all.

I hear that in the UK, there is something called the "Higher Doctorate" and is suppose to be bigger than a Ph.D, what about that? I know I am being a bit a impolite, but I am just confused, that is all

I hear that in the UK, there is something called the "Higher Doctorate" and is suppose to be bigger than a Ph.D, what about that?

It seems like you're talking about when a university awards an honorary doctorate to someone who didn't necessarily study at the university giving him/her the honor. It's like if you get your Ph.D at school a but you happen to be very well known so schools b, c, and d would like to give you recognition by giving you an honorary doctorate.
Example: Dr. Flyingpig received his Ph.D from school a. He also has an honorary doctorate from school b, c, and d.

It seems like you're talking about when a university awards an honorary doctorate to someone who didn't necessarily study at the university giving him/her the honor. It's like if you get your Ph.D at school a but you happen to be very well known so schools b, c, and d would like to give you recognition by giving you an honorary doctorate.
Example: Dr. Flyingpig received his Ph.D from school a. He also has an honorary doctorate from school b, c, and d.

Many countries have a post-doctorate degree which is what he is talking about; it's essentially another step after the Ph.D and requires a very high standard thesis which is published with a lot of positive recognition.

So my question is, if a person has a Ph.D in Chemistry, Physics, Mathematics, and Biology, would he or she be able to do a job normally needed for a Engineer that requires a Ph.D?

Or can someone with a Ph.D in Physics and Mathematics would be able to do an Engineer's job?

If not, why? If being a wielder of a Ph.D, doesn't that mean he or she should know everything in that field? And since Engineering is part of that, should he or she be able to do that job without the need for the degree?

I think the issue of being an engineer is similar to being a writer or an artist. If you do it, then you are it. Perhaps the same could be said of physics and other sciences too, but maybe less so. I think of Einstein publishing great works as a patent clerk, but maybe that's not a fair example.

A key thing about engineering is experience in the field of expertise. Whatever the background of a person, an inexperienced person should not be designing devices that can put people in danger. Nor should they be designing products that will be mass produced, since a mass recall due to failures could put a company out of business.

My father worked as an engineer with a history degree with minor in physics. I think you see this kind of thing less today, but there are no hard and fast rules. Inborn ability is a key ingredient to making a good engineer, and there are many degreed engineers that I wouldn't trust to design a toaster, never mind help put a man on the moon.

As far as a PhD, I think it represents a demonstration of intelligence, determination, ability to focus, training in research techniques, ability to learn, ability to self-teach, passion and detailed knowledge in a specialized field. However, a person can have and/or develop all of these very good things without a Ph.D.

But it would really depend on the job. A PhD in math or physics would not be adequate to do any type of detailed mechanical or structural design from scratch. It would be sufficient for design testing or analysis perhaps.